25605419840 has 672 divisors, whose sum is σ = 84903624960. Its totient is φ = 7195668480.

The previous prime is 25605419821. The next prime is 25605419887. The reversal of 25605419840 is 4891450652.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 25605419791 and 25605419800.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 595474859 + ... + 595474901.

It is an arithmetic number, because the mean of its divisors is an integer number (126344680).

Almost surely, 2^25605419840 is an apocalyptic number.

25605419840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25605419840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42451812480).

25605419840 is an abundant number, since it is smaller than the sum of its proper divisors (59298205120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25605419840 is a wasteful number, since it uses less digits than its factorization.

25605419840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 44.

The spelling of 25605419840 in words is "twenty-five billion, six hundred five million, four hundred nineteen thousand, eight hundred forty".